Regarding ‘your about waist level’, I’m a little bit more in doubt. And that’s mainly because of the waist coat. If you normally are wearing one, it is OK, but if you never do, why with the kilt?
My reason for going with the waistcoat is because I want to make a good first impression. You're correct in that I never wear one otherwise, and nobody around here does either. But it does make the entire outfit look a bit dressier than it would look without it. So when introducing my coworkers and my boss to the kilt, I'd rather look overdressed than underdressed. Later on, once they're used to the kilt, I can take a more casual approach.

Even ties are not normally worn here. We voluntarily wear them once a week, which is a trend I started in this office and has caught on with almost all the men who work here. On Tuesdays we wear ties, just for the sake of looking nice and being professional. Considering that I started that trend, I think it will go a long way toward others accepting the kilt in the office, since they know that I favor tradition and dressing more nicely than I'm required to.

Come to think of it, I heartily despise the trend towards casual wear in a professional environment. Nowadays, it seems that what passes for 'professional' clothing is slacks and a polo-style shirt. I really wish we could go back a couple of generations to where men wore ties and jackets as the norm, as a more traditional look. And hats. Men don't wear hats with suits any more, which is a bit of a shame. A kilted outfit at the "day wear" or "smart day wear" level would fit in a lot better if the rest of society were actually interested in looking nice too, instead of scraping by with casual/comfortable clothing.